# US 12,004,233 B2 · Method and apparatus for random access in NTN > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,233 B2 - Document ID: US12004233B2 - Status: Granted - Kind: B2 - Application number: 17/500,839 - Filed: 2021-10-13 - Published: 2022-04-21 - Granted: 2024-06-04 - Earliest claimed: 2020-10-16 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Kyeongin Jeong; Nishithkumar D. Tripathi - Web page: https://patentgrep.com/patent/US12004233B2 ## CPC - H04W 74/0841: {with collision treatment} - H04B 7/18513: {Transmission in a satellite or space-based system} - H04W 28/0226: {based on location or mobility (handoff or reselection H04W36/00; mobile application services making use of the location of users or terminals H04W4/02)} - H04W 56/005: {compensating for timing error by adjustment in the receiver} - H04W 72/02: Selection of wireless resources by user or terminal - H04W 72/51: based on terminal or device properties - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 74/0866: {using a dedicated channel for access} - H04W 56/0045: {compensating for timing error by altering transmission time} - H04W 80/02: Data link layer protocols - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION ## Abstract Methods and apparatuses of UE for performing random access procedures in NTN. A method of a UE comprises: identifying configuration information including a first and second set of resources for a RACH operation; determining whether current location information of the UE is valid for the RACH operation; selecting the first set of resources based on a determination that the current location information of the UE is valid; selecting the second set of resources based on a determination that the current location information of the UE is invalid; transmitting a RACH preamble on the selected first or second set of resources; and receiving, in response to transmitting the RACH preamble, a RAR MAC PDU. The RAR MAC PDU includes a MAC subPDU comprising a first format of MAC subPDU associated with the first set of resources and a second format of MAC subPDU associated with the second set of resources. ## Claims ### Claim 1 A user equipment (UE) in a wireless communication system, the UE comprising: a processor configured to: identify configuration information including a first set of resources and a second set of resources for a random access channel (RACH) operation, determine whether current location information of the UE is valid for the RACH operation, select the first set of resources based on a determination that the current location information of the UE is valid, and select the second set of resources based on a determination that the current location information of the UE is invalid; and a transceiver operably coupled to the processor, the transceiver configured to: transmit a RACH preamble on the selected first or second set of resources, and receive, in response to transmission of the RACH preamble, a random access response (RAR) medium access control protocol data unit (MAC PDU) (RAR MAC PDU), wherein the RAR MAC PDU includes a MAC subPDU comprising a first format of MAC subPDU associated with the first set of resources and a second format of MAC subPDU associated with the second set of resources. ### Claim 2 (depends on 1) The UE of claim 1, wherein the processor is further configured to: select the RACH preamble from a first set of RACH preambles configured for the first set of resources; or select the RACH preamble from a second set of RACH preambles configured for the second set of resources. ### Claim 3 (depends on 1) The UE of claim 1, wherein the processor is further configured to: select a RACH frequency from a first set of RACH frequencies configured for the first set of resources; or select the RACH frequency from a second set of RACH frequencies configured for the second set of resources. ### Claim 4 (depends on 1) The UE of claim 1, wherein the processor is further configured to: select a RACH time instance from a first set of RACH time instances configured for the first set of resources; or select the RACH time instance from a second set of RACH time instances configured for the second set of resources. ### Claim 5 (depends on 1) The UE of claim 1, wherein the processor is further configured to: determine whether a value of a RAPID field included in the MAC subPDU indicates the first set of resources or the second set of resources; decode the first format of the MAC subPDU based on a determination that the value of the RAPID field included in the MAC subPDU indicates the first set of resources; and decode the second format of the MAC subPDU based on a determination that the value of the RAPID field included in the MAC subPDU indicates the second set of resources. ### Claim 6 (depends on 1) The UE of claim 1, wherein the processor is further configured to: determine whether a value of a reserved (R) field included in the MAC subPDU indicates the first set of resources or the second set of resources; decode the first format of the MAC subPDU based on a determination that the value of the R field included in the MAC subPDU indicates the first set of resources; and decode the second format of the MAC subPDU based on a determination that the value of the R field included in the MAC subPDU indicates the second set of resources. ### Claim 7 (depends on 1) The UE of claim 1, wherein: the transceiver is further configured to receive a physical downlink control channel (PDCCH) including a random access-radio network temporary identification (RA-RNTI) that is used to schedule a reception of the RAR MAC PDU; and the processor is further configured to: determine whether the RA-RNTI included in the PDCCH indicates the first set of resources or the second set of resources, decode the first format of the MAC subPDU based on a determination that the RA-RNTI indicates the first set of resources, and decode the second format of the MAC subPDU based on a determination that the RA-RNTI indicates the second set of resources. ### Claim 8 (depends on 1) The UE of claim 1, wherein: the first format of the MAC subPDU includes a first length of a timing advance (TA) command field and the second format of the MAC subPDU includes a second length of a TA command field; and the second length of the TA command field is longer than the first length of the TA command field. ### Claim 9 (depends on 1) The UE of claim 1, wherein: a value of a timing advance (TA) command field in the first format of the MAC subPDU is identified using a first granularity, and the value of the TA command field in the second format of the MAC subPDU is identified using a second granularity. ### Claim 10 A method of operating a user equipment (UE), the method comprising: identifying configuration information including a first set of resources and a second set of resources for a random access channel (RACH) operation; determining whether current location information of the UE is valid for the RACH operation; selecting the first set of resources based on a determination that the current location information of the UE is valid; selecting the second set of resources based on a determination that the current location information of the UE is invalid; transmitting a RACH preamble on the selected first or second set of resources; and receiving, in response to transmitting the RACH preamble, a random access response (RAR) medium access control protocol data unit (MAC PDU) (RAR MAC PDU), wherein the RAR MAC PDU includes a MAC subPDU comprising a first format of MAC subPDU associated with the first set of resources and a second format of MAC subPDU associated with the second set of resources. ### Claim 11 (depends on 10) The method of claim 10, further comprising: selecting the RACH preamble from a first set of RACH preambles configured for the first set of resources or the RACH preamble from a second set of RACH preambles configured for the second set of resources; selecting a RACH frequency from a first set of RACH frequencies configured for the first set of resources or the RACH frequency from a second set of RACH frequencies configured for the second set of resources; and selecting a RACH time instance from a first set of RACH time instances configured for the first set of resources or the RACH time instance from a second set of RACH time instances configured for the second set of resources. ### Claim 12 A base station (BS) in a wireless communication system, the BS comprising: a processor configured to generate configuration information including a first set of resources and a second set of resources for a random access channel (RACH) operation; and a transceiver configured to: transmit the configuration information including the first set of resources and the second set of resources for the RACH operation, receive a RACH preamble on the first or second set of resources; and transmit, in response to receiving the RACH preamble, a random access response (RAR) medium access control protocol data unit (MAC PDU) (RAR MAC PDU), wherein the RAR MAC PDU includes a MAC subPDU comprising a first format of MAC subPDU associated with the first set of resources and a second format of MAC subPDU associated with the second set of resources, and wherein the first set of resources is for when current location information of a user equipment (UE) is valid and the second set of resources is for when the current location information of the UE is invalid. ### Claim 13 (depends on 12) The BS of claim 12, wherein: the RACH preamble is from a first set of RACH preambles configured for the first set of resources; or the RACH preamble is from a second set of RACH preambles configured for the second set of resources. ### Claim 14 (depends on 12) The BS of claim 12, wherein: a RACH frequency is from a first set of RACH frequencies configured for the first set of resources; or the RACH frequency is from a second set of RACH frequencies configured for the second set of resources. ### Claim 15 (depends on 12) The BS of claim 12, wherein: a RACH time instance is from a first set of RACH time instances configured for the first set of resources; or the RACH time instance is from a second set of RACH time instances configured for the second set of resources. ### Claim 16 (depends on 12) The BS of claim 12, wherein: the processor is further configured to generate the MAC subPDU including a value of a RAPID field, the value of the RAPID field included in the MAC subPDU indicating the first set of resources or the second set of resources; the first format of the MAC subPDU is decoded based on that the value of the RAPID field included in the MAC subPDU indicates the first set of resources; and the second format of the MAC subPDU is decoded based on that the value of the RAPID field included in the MAC subPDU indicates the second set of resources. ### Claim 17 (depends on 12) The BS of claim 12, wherein: the processor is further configured to generate the MAC subPDU including a value of a reserved (R) field, the value of the R field included in the MAC subPDU indicates the first set of resources or the second set of resources; the first format of the MAC subPDU is decoded based on that the value of the R field included in the MAC subPDU indicates the first set of resources; and the second format of the MAC subPDU is decoded based on that the value of the R field included in the MAC subPDU indicates the second set of resources. ### Claim 18 (depends on 12) The BS of claim 12, wherein: the transceiver is further configured to transmit a physical downlink control channel (PDCCH) including a random access-radio network temporary identification (RA-RNTI) that is used to schedule a reception of the RAR MAC PDU, the RA-RNTI included in the PDCCH indicating the first set of resources or the second set of resources; the first format of the MAC subPDU is decoded based on that the RA-RNTI indicates the first set of resources; and the second format of the MAC subPDU is decoded based on that the RA-RNTI indicates the second set of resources. ### Claim 19 (depends on 12) The BS of claim 12, wherein the processor is further configured to generate the first format of the MAC subPDU including a first length of a timing advance (TA) command field and the second format of the MAC subPDU including a second length of a TA command field, the second length of the TA command field being longer than the first length of the TA command field. ### Claim 20 (depends on 19) The BS of claim 19, wherein: a value of a timing advance (TA) command field in the first format of the MAC subPDU is identified using a first granularity, and the value of the TA command field in the second format of the MAC subPDU is identified using a second granularity.